Multiple electrical fuse



w. J. MANNING MULTIPLE ELECTRICAL FUSE Nov. 24, 1931,

Filed June 24 n f4? z .1 w M v u .7 1 r a JV 5 J Patented Nov. 24, 1931PATENT OFFICE -W'ILLIAM OSEPH MANNING, F PHILADELPHIA, PENNSYLVANIAMULTIPLE ELECTRICAL FUSE Application filed June 24,

As hereinafter described,my invention is applicable to structures of therotary screw plug type, adapted to fit a standard incandescent lampsocket, having two terminals 5 like an ordinary incandescent lamp bulb,and includinga rotaryfusible metal plate with a circular series ofmembers adapted to be turned to successively bridge the gap between Psaid terminals. Ordinarily, fuses of that type are so constructed andarranged that when the series of fuse members have been successivelyfused, the entire structure must be discarded. Therefore, it is theobject and effect of my invention .to provide such a fuse structurewherein the fuse element may be readily removed and replaced byanothersimilar element at minimum cost and without loss. of the remainder ofthe structure.

My invention includes the various novel features of construction andarrangement hereinafter more definitely specified.

In said. drawings: Fig. I is an axial end elevation of a fuse structureconveniently embodying my invention. Fig. II is a side elevation ofthestructure shown in Fig. I.

-Fig. III is an inside. elevation of the rotatable cap, of which theoutside is shown in Fig. I. Fig. IV is alongitudinal, diametrical,sectional view of said structure shown igs i Fi 1 and II. Fig. V is anouter face elevation of the rotary disk which carries the fusibleelement in said structure. Fig. VI is an edge elevationof said diskshown in .Fig. V. Fig. VII is an inner face elevation .of said diskshown in Figs. V and VI VIII.is a view similarto Fig. VII, but show-.ing a modified form of fusible element. Fig. IX is a fragmentaryelevation of the rotary screw plug indicated in FigsJII and IV showinginterrupted screw meansfor clamping the fusible member in adjustedposition in said plug.

In said figures; the bodyl isformed of dielectric material suchasporcelain, bakelite, or other material which may be molded. Saidbody 1carries the metallic contact screw 2 having the electric terminal 3electrically connected therewith, and having its contact end4'terminating in eccentric relation with the axis of rotation of saidscrew. Said body 1929 Serial No. 373,335.

1 also has the metallic contact ring 6 in coaxlal relation therewith andelectrically con 'nected with the terminal 7, the end 8 of whichterminates in the same plane as the end 4 of the terminal 3. Saidcontact 6 and its terminal -7 are held in rigid relation with said body1' by the tubular rivet 9. Said contacts 2 and 6, and their respectiveterminals 3 and '7, are insulated from each other by the ring pluralityof radial members 16, each adapted to successively bridge said terminalends 4 and 8, in respectively different positions of rotation of saiddisk. Said fuse element 14 is connected with the rotary disk 13 and isdisr carded therewith. Y

' The rotarycap 18 is fitted to revolve on said body-1, andadapted toengage said disk'13 to turn with said cap; said cap having the coaxialopening 19 fitted to the coaxial projection 20 of said disk, saidopening 19 and projection 2O conveniently including a circular series ofsix points, respectively coinciding with said radial members 16 so thatthe latter are visible thru said cap opening 19 and the C transparentmaterial of said disk 13. I find it convenient to provide said disk 13with recesses 22, which are slightly undercut, so as to securely holdthe fusible plate 14 and its radial members 16, when said plate ispressed therein; said members being initially concavo convex, asindicated by the dotted line in Fig. VI.

I find it convenient to provide means adapted to detachably connect saidbody 1 and cap 18 so that said cap may be removed and replaced tosuccessively release and hold such disks 13, in cooperative relationwith said electric terminals. Such means may include a circular seriesof detent notches 24 in the outwardly projecting circumferential flange25 on said body 1, forming sectors of an interrupted female screw threadon said body and circular series of inwardly pressed detent springs 26on said cap 18. Said springs 26 form sectors of an interrupted malescrew thread on said cap. Said flange 25 is conically tapered asindicated in Fig. IV and the inner faces of said detent springs 26 aresimilarly inclined, so that the resilience of said springs 26 not onlytends to hold the cap 18 and disk 18 in any rotary position to whichthey may be turned, with said springs 26 in registry with respectivenotches 24:, but the inclination of said springs 26 and flange 25 causessaid cap 18 to be stressed axially toward Laid body 1, to resilientlypress said fusible members 14 in good contact with the ends 4 and 8 ofsaid terminals 3 and 7. Moreover, the provision of the coordinatedsectoral screw thread members aforesaid permits said cap to be removedand replaced, by a fraction of a revolution thereof, to successivelyrelease and hold such disks 13, which, as shown, are imperforate andserve to seclude the fusible plates 14 from the outer atmosphere.

Although, as indicated in Fig. VII, the radial fuse members 16 extendoutwardly from an axial portion of the plate 1 1; they may be otherwisedisposed, for instance, as indicated in Fig. VIII, the radialprojections 28 extend inwardly from the annular fuse plate 29. Moreover,as indicated in Fig. IX, the flange 25 on said body 1 may be formed asan interrupted screw thread having helieally inclined portions 31 forengagement with the detent springs 26 so as to make it possible tostress the cap 18 more forcibly toward said body 1 than by the mereresilience of said springs 26 engaging the conically inclined perimeterof said flange 25.

Therefore, I do not desire to limit myself to the precise details ofconstruction and arrangement herein set forth, as it is obvious thatvarious modifications may be made therein without departing from theessential features of my invention, as defined in the appended claims.

I claim:

1. I11 a multiple electrical fuse; the combination with a body includingmeans rigidly supporting a pair of electrical terminals, in insulated,parallel spaced relation, and terminating in the same plane; of animperforate rotary disk, of transparent insulating material, mounted torotate on said. body, and having, inseparably fixed thereon, a plate offusible metal comprising a plurality of members, each adapted tosuccessively bridge said terminalsin respectively different positions ofrotation of said disk; a rotary cap fitted to revolve on said body, andadapted to detachably engage said disk to turn with said cap; and meansadapted to detachably connect said body and cap; whereby said plate issecluded from the outer atmosphere by said disk and said cap may beremoved and replaced to successively release and hold such disks, incooperative relation with said terminals.

2. In a multiple electrical fuse; the combination with a body having, inunitary relation therewith, screw means adapted to engage a cap of apair of electrical terminals, in spaced relation; an imperforate rotarydisk, mounted to rotate on said body, and having inseparably fixedthereon, in insulated relation, a plurality of fuse members, eachadapted to successively bridge said terminals in respectively differentpositions of rotation of said disk; a rotary metal cap fitted to revolveon said body, and adapted to engage said disk to turn with said cap; andscrew means, in unitary relation with said cap, adapted to detachablyconnect said body and cap; whereby said cap may be removed and replacedto suecessively release and hold such disks, in cooperative relationwith said terminals.

3. In a multiple electrical fuse; the combination with a screw threadedbody of insulating material, including means rigidly supporting a pairof electrical terminals, in insulated spaced relation and terminating inthe same plane; of a rotary disk, of transparent glass, mounted torotate on said body,

and carrying, inseparably fixed thereon, a plate of fusible metalcomprising a plurality of radial members, each adapted to successivelybridge said terminals in respectively different positions of rotation ofsaid disk; a screw threaded rotary cap fitted to revolve on said body,and adapted to detachably engage said disk to turn with said cap; andmeans, including metal springs on said cap, adapted to detachablyconnect said body and cap; whereby said cap may be removed and replacedto successively release and hold such disks, inresilient cooperativerelation with said terminals.

4-. In a multiple electrical fuse; the combination with a body having apair of electrical terminals, in spaced relation, and terminating in thesame plane; of a rotary disk, of insulating material, mounted to rotateon said body, and having inseparably fixed thereon, in insulatedrelation, a plate of fusible metal comprising a plurality of members,ach adapted to successively bridge said terminals in respectivelydifferent positions of rotation of said disk; a rotary cap fitted torevolve on said body, and adapted to engage said disk to turn with saidcap; and means, including sectoral screw thread projections on said capand sectoral screw thread recesses in said body, whereby said cap may beremoved and replaced to successively release and hold such disks, incooperative relation with said terminals.

5. In a multiple electrical fuse; the combination with a body having apair of electrical terminals, in spaced relation, and terminating in thesame plane; of a rotary disk, of insulating material, mounted to rotateon said body, and carrying a plate of fusible metal comprising aplurality of members, each adapted to successively bridge said terminalsin respectively different positions of rotation of said disk; a rotarycap fitted to revolve on said body, and adapted to engage said disk toturn with said cap; and means, including interrupted screw threads onsaid body and cap, adapted to detachably connect said body and cap;whereby said cap may be removed and replaced, by a fraction of arevolution thereof, to successively release and hold such disks, incooperative relation with said terminals.

6. In a multiple fuse structure, the combination with a rotary disk ofinsulating material, having a polygonal projection in coaxial relationtherewith, and adapted to carry a fuse plate; of a rotary cap having apolygonal opening in coaxial relation therewith adapted to detachablyengage said disk to turn with said cap.

7. In a fuse structure, the combination with a body of insulatingmaterial having a circular recess at one end thereof and elec-- trioterminals projecting into said recess in spaced relation; of a rotarydisk of insulating material adapted to turn in said recess; a fusibleelement inseparably fixed on said disk, adapted to bridge the gapbetween said terminals when in registry therewith; and distant springmeans adapted to hold said fusible element in contact with saidterminals.

8. In a fuse structure, the combination with a sectorally screw threadedbody of insulating material; of a disk of insulating material mounted toturn on said body; and a sectorally screw threaded cap mounted tofrotateon said body, having means adapted to detachably engage said disk andsaid body.

9. In a fuse structure; an imperforate rotary disk of transparent glasscarrying a plate of fusible metal.

10. A- structure as in claim 9; wherein the glass disk is recessed andsaid fusible metal pressed in such recess to hold the same, ininseparable relation therewith.

11. An insulating body for a fuse structure having an interrupted'femalescrew thread at one end thereof, with radially projecting portionsbetween the sectors of said thread.

In testimony whereof, I have hereunto signed my name at Philadelphia,Pennsylvania, this twenty-first day of June, 1929.

WILLIAM JOSEPH MANNING.

